Chapter 18 - Digestive System Flashcards
The digestive system is also known as the…
GI Tract or Alimentary Canal
What structures are included in the digestive system (not including accessory structures)
oral cavity (mouth), pharynx, larynx, esophagus, stomach, small intestine (SI), large intesting (LI), cecum, rectum
What structures does food NOT pass through?
accessory structures
What are the accessory structures of the digestive system?
What are all of its general function?
teeth, tongue, salivary gland, liver, gall bladder, pancreas
aid in digestion
What is the function of the digestive system?
breakdown/digest large biomolecules (carbohydrates, fats, proteins) in food into smaller, absorbable substances (moves into blood vessel)
Give some examples of large biomolecules
What are they broken down into?
Where are the absorbed into?
What is it used by?
proteins ➜ amino acids (small) ➜ absorbed into blood stream ➜ used by cells
carbohydrates ➜ monosaccharides (ex. glucose; small) ➜ absorbed into blood stream ➜ used by cells
TRUE or FALSE: Proteins and carbohydrates can be absorbed into the bloodstream
False, proteins and carbohydrates are large biomolecules that need to be broken down into small subunits in order to be absorbed into the bloodstream
Why do biomolecules need to be broken down/digested in order to be absorbed?
Biomolecules are too large to be absorbed, so they must be broken down into smaller absorbable units
Name the steps of food processing in order
ingestion
digestion
absorption
elimination
Describe ingestion
taking food into the mouth
Describe digestion
TWO TYPES OF DIGESTION
mechanical (physical) digestion: occurs by chewing and stomach muscle contractions
chemical digestion: breaksdown biomolecules into small compounds by chemical reactions; reequires an enzyme
Describe absorption
small, broken down substances enter bloodstream; occurs mainly at SI
Describe elimination
undigested material exits the body as poop
What part of the digestive system absorbs mostly nutrients?
small intestine (SI)
What part of the digestive system absorbs mostly water (H2O)?
large intestine (LI)
Name the 2 types of digestion and state where each occurs in the body
Mechanical digestion
In oral cavity/mouth by mastication (chewing) of teeth
In stomach by contraction of stomach muscle
Chemical Digestion
In oral cavity/mouth by saliva (salivary amylase)
In stomach by enzyme pepsin
What is mastication and what is its purpose
Mastication = chewing
Aids in mechanical digestion to breakdown food into small substances for swallowing and mixes it with saliva
What salivary glands produce saliva?
sublingual gland
submandibular gland
parotid gland
What does saliva contain?
mostly H2O
mucus
antimicrobial agents (to kill microbes)
salivary amylase (enzyme to breakdown starch/carbs)
What does salivary amylase function in? What does it do?
enzyme that helps with chemical digestion
breaks down starches/carbs